Segment Information (Tables)

12 Months Ended

Dec. 31, 2013

Segment Reporting [Abstract]

Accounts Receivable for Services

Accounts receivable for these services, which are not eliminated during consolidation, are presented in the table below (in thousands).

	December 31, 2013		December 31, 2012
Accounts receivable for NPL services	$	10,787	$	8,179

Schedule of Segment Reporting Information

The financial information pertaining to the natural gas operations and construction services segments for each of the three years in the period ended December 31, 2013 is as follows (thousands of dollars):

2013	Gas Operations		Construction Services		Adjustments (a)				Total
Revenues from unaffiliated customers	$	1,300,154	$	562,475					$	1,862,629
Intersegment sales		—		88,153						88,153
Total	$	1,300,154	$	650,628					$	1,950,782
Interest revenue	$	456	$	5					$	461
Interest expense	$	62,555	$	1,145					$	63,700
Depreciation and amortization	$	193,848	$	42,969					$	236,817
Income tax expense	$	65,377	$	12,565					$	77,942
Segment net income	$	124,169	$	21,151					$	145,320
Segment assets	$	4,272,029	$	293,811	$	(666	)		$	4,565,174
Capital expenditures	$	314,578	$	49,698					$	364,276
2012	Gas Operations		Construction Services		Adjustments				Total
Revenues from unaffiliated customers	$	1,321,728	$	522,676					$	1,844,404
Intersegment sales		—		83,374						83,374
Total	$	1,321,728	$	606,050					$	1,927,778
Interest revenue	$	915	$	9					$	924
Interest expense	$	66,957	$	1,063					$	68,020
Depreciation and amortization	$	186,035	$	37,387					$	223,422
Income tax expense	$	64,973	$	10,303					$	75,276
Segment net income	$	116,619	$	16,712					$	133,331
Segment assets	$	4,204,948	$	283,109					$	4,488,057
Capital expenditures	$	308,951	$	86,761					$	395,712
2011	Gas Operations		Construction Services		Adjustments		Total
Revenues from unaffiliated customers	$	1,403,366	$	391,701			$	1,795,067
Intersegment sales		—		92,121				92,121
Total	$	1,403,366	$	483,822			$	1,887,188
Interest revenue	$	465	$	20			$	485
Interest expense	$	68,777	$	825			$	69,602
Depreciation and amortization	$	175,253	$	25,216			$	200,469
Income tax expense	$	49,576	$	13,727			$	63,303
Segment net income	$	91,420	$	20,867			$	112,287
Segment assets	$	4,048,613	$	227,394			$	4,276,007
Capital expenditures	$	305,542	$	75,449			$	380,991

(a) Construction services segment assets include income taxes payable of $666,000 in 2013, which was netted against gas operations segment income taxes receivable, net during consolidation.